From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Wed, 05 Mar 2025 15:03:54 +0100 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1tppLm-00ACra-2O for lore@lore.pengutronix.de; Wed, 05 Mar 2025 15:03:54 +0100 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1tppLl-0008Sd-By for lore@pengutronix.de; Wed, 05 Mar 2025 15:03:54 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: Content-Transfer-Encoding:Content-Type:In-Reply-To:From:References:To:Subject :MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=DXHymkxwlVMG/+efbS95izwJIlqitZzfTy1ZKNN5Un0=; b=m8VJs6hqPDQ2fO hH8xv0T9ZsTkq0XdVzPTnWo2ZphRe81a0FBbsdAYbvzIjkQAFEKoX+Iw1VqOd8WnwQeblQMl3qJ9/ h+QxSmJGNVr0ZaRyqDweOKYDBC2WiaaUZKfTlMks1Z7M/awZJpNtHF9Lj/Kpolf8yGOk658l3WJpc Gxhg5UfEg39yZmHBVZ0o1WPVKiyLF28hDm6NIfrbr5IOBYeiu3NUn4lMTA6AaaC1/pc14Dl39DZoY 94hleeKUr9joHGbhsv3m48WnX3ANUWwKTXTzM/zu4ZzE/q0bkzlfyEeXlqKD5SRXO33yMGOggoqxe dBO2qD3gcwVO2TqMC3LQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tppLa-00000008HE4-20Pg; Wed, 05 Mar 2025 14:03:42 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tpoE6-000000085Am-3dJP for barebox@lists.infradead.org; Wed, 05 Mar 2025 12:51:56 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1tpoE3-0005C9-OQ; Wed, 05 Mar 2025 13:51:51 +0100 Message-ID: <7b73bca5-c1a2-4260-9c8a-510887ba4be8@pengutronix.de> Date: Wed, 5 Mar 2025 13:51:51 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: David Jander , Martin Wege References: <3ba4d5f3-9679-4a32-a3e7-a8c958107df9@pengutronix.de> <20250305123032.2b2c7768@erd003.prtnl> Content-Language: en-US From: Ahmad Fatoum In-Reply-To: <20250305123032.2b2c7768@erd003.prtnl> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250305_045154_914671_85344C8B X-CRM114-Status: GOOD ( 36.18 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Barebox List , Cedric Blancher , Dan Shelton Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-5.2 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: Mount NFSv4.2 filesystem in barebox? X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) Hi David, On 05.03.25 12:30, David Jander wrote: > On Tue, 4 Mar 2025 22:50:00 +0100 > Martin Wege wrote: >> So yes, you would have customers for NFSv4.1 support in barebox. > > Just wanted to chime in to amplify this a bit, since we are also using NFSv4.2 > netboot (though only TFTP in barebox for now): > > Your arguments are solid, and make a lot of sense. If you are going to replace > more and more microcontroller based nodes with Linux capable SoCs, because it > makes a lot of economical sense (hardware costs are very similar nowadays, and > software development is 10x easier and cheaper on Linux than on a uC), you > will end up inevitably with a lot of Linux nodes inside of a machine or > industrial plant, where you previously had uC's. So, do you want to continue > using 1970's tech (RS485/modbus) or 1980's tech (CAN) to communicate between all > those nodes, or will you use Linux's native language (TCP/IP) which also > immediately means another 10x reduction in software development costs of the > networking part? If you choose the latter, you will also get significant HW > cost savings basically for free if you also net-boot (via NFS and/or TFTP). > > In other words, why are we not already doing this? > > At least we are. We are starting to use Single Pair Ethernet almost everywhere > where there were other field-busses involved traditionally. So we noticed that > we end up with a lot of boards running Linux connected together via anything > from 10Base-T1L to 1000Base-T1. Replace the eMMC chip on all but one of them > with a cheap 2MiB SPI-NOR flash to load barebox and netboot from one single > board running an NFSv4.2 (and TFTP) server serving the kernel and rootfs for > all the others from a single eMMC, that can be updated with a single RAUC > bundle guaranteeing consistent software and trivially easy updates on all > nodes at once. Not to mention the benefit of trivial repairs because all > boards are basically dumb and don't need to be flashed with software that > matches the machine they are being replaced in, etc... Which I think is very cool. :-) > To be fair though, it isn't strictly needed for barebox to have NFS support > for our use-case, since it suffices to load the kernel (and possibly an > initramfs) via TFTP and mount the nfsroot from the kernel, but IMHO it is > certainly valuable to have basic NFSv4.2 support in barebox. It would > facilitate the use of just 1 protocol instead of 2. Ack. > I also agree that NFSv3 > support in that regard offers little value since you really don't want to base > everything on this obsolete version with all of its limitations. > > But also a bit of caution to be mindful of: Cybersecurity. Of course barebox > can be made to only boot signed fit images, but are there other potential > attack vectors? We have been fuzzing the security critical boot path and issues were found and fixed. Our network stack and NFS implementation are not currently part of that. The documentation now spells that out and explicitly advises against using any unsigned file system at all (whether networked or not) to contain a signed FIT image: https://www.barebox.org/doc/latest/user/security.html#avoiding-use-of-file-systems As we gain more confidence in the implementation (or rather import mptcp and focus on fuzzing that), this will change, but as things stand now, it's is not advisable to do network boot of signed images. > What if the NFS server needs to be secured with with GSS and > kerberos? Barebox possibly won't be able to access it unless it also supports > that. Yes. I think HTTP(S) support may be a better investment of time, even if it means having to use two protocols still. > P.S.: I am currently not subscribed to the barebox mailing list, so I don't > know if this email will get forwarded by the list server. The ML accepts mails from non-subscribers. Infradead is currently slow on delivering mail, though, but I hope it will soon show up on both lore.barebox.org/barebox and lore.kernel.org/barebox. Cheers, Ahmad > > Best regards, > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |